Biocon is likely to sell a portion of its 69.99 percent stake in Syngene International, a contract research and manufacturing firm, sources have told CNBC-TV18.

Biocon, an Indian biopharmaceutical company, is likely to sell its shares in a block deal on the open market.

Apart from Biocon promoters, Biocon Limited Employee Welfare Trust holds 0.29 percent stake in Syngene International, taking the total stake to about 70.29 percent.

The deal will most likely take place at a discount of up to 5 percent. Further information on the deal is awaited.

On September 5, shares of Syngene International ended the day at Rs 578.75, down 2.56 percent from the previous close.

The stock had touched an intraday low of Rs 575.5, down 3.11 percent. Biocon shares also ended the day at BSE down about a percent. 

Syngene stock has been losing for the last four days and has fallen 4.16 percent in returns in the period.